diff --git a/docs/advanced_features/server_arguments.md b/docs/advanced_features/server_arguments.md
index 195178689..0f1a327c9 100644
--- a/docs/advanced_features/server_arguments.md
+++ b/docs/advanced_features/server_arguments.md
@@ -218,7 +218,7 @@ Please consult the documentation below and [server_args.py](https://github.com/s
 | `--file-storage-path` | The path of the file storage in backend. | `sglang_storage` | Type: str |
 | `--enable-cache-report` | Return number of cached tokens in usage.prompt_tokens_details for each openai request. | `False` | bool flag (set to enable) |
 | `--reasoning-parser` | Specify the parser for reasoning models. Supported parsers: [deepseek-r1, deepseek-v3, glm45, gpt-oss, kimi, qwen3, qwen3-thinking, step3]. | `None` | `deepseek-r1`, `deepseek-v3`, `glm45`, `gpt-oss`, `kimi`, `qwen3`, `qwen3-thinking`, `step3` |
-| `--tool-call-parser` | Specify the parser for handling tool-call interactions. Supported parsers: [deepseekv3, deepseekv31, glm, glm45, glm47, gpt-oss, kimi_k2, llama3, mistral, pythonic, qwen, qwen25, qwen3_coder, step3]. | `None` | `deepseekv3`, `deepseekv31`, `glm`, `glm45`, `glm47`, `gpt-oss`, `kimi_k2`, `llama3`, `mistral`, `pythonic`, `qwen`, `qwen25`, `qwen3_coder`, `step3` |
+| `--tool-call-parser` | Specify the parser for handling tool-call interactions. Supported parsers: [deepseekv3, deepseekv31, glm, glm45, glm47, gpt-oss, kimi_k2, llama3, mistral, pythonic, qwen, qwen25, qwen3_coder, step3]. | `None` | `deepseekv3`, `deepseekv31`, `glm`, `glm45`, `glm47`, `gpt-oss`, `kimi_k2`, `llama3`, `mistral`, `pythonic`, `qwen`, `qwen25`, `qwen3_coder`, `step3`, `gigachat3` |
 | `--tool-server` | Either 'demo' or a comma-separated list of tool server urls to use for the model. If not specified, no tool server will be used. | `None` | Type: str |
 | `--sampling-defaults` | Where to get default sampling parameters. 'openai' uses SGLang/OpenAI defaults (temperature=1.0, top_p=1.0, etc.). 'model' uses the model's generation_config.json to get the recommended sampling parameters if available. Default is 'model'. | `model` | `openai`, `model` |
 
diff --git a/python/sglang/srt/function_call/function_call_parser.py b/python/sglang/srt/function_call/function_call_parser.py
index e7fdd6398..2f562192e 100644
--- a/python/sglang/srt/function_call/function_call_parser.py
+++ b/python/sglang/srt/function_call/function_call_parser.py
@@ -14,6 +14,7 @@ from sglang.srt.function_call.core_types import ToolCallItem
 from sglang.srt.function_call.deepseekv3_detector import DeepSeekV3Detector
 from sglang.srt.function_call.deepseekv31_detector import DeepSeekV31Detector
 from sglang.srt.function_call.deepseekv32_detector import DeepSeekV32Detector
+from sglang.srt.function_call.gigachat3_detector import GigaChat3Detector
 from sglang.srt.function_call.glm4_moe_detector import Glm4MoeDetector
 from sglang.srt.function_call.glm47_moe_detector import Glm47MoeDetector
 from sglang.srt.function_call.gpt_oss_detector import GptOssDetector
@@ -67,6 +68,7 @@ class FunctionCallParser:
         "trinity": TrinityDetector,
         "interns1": InternlmDetector,
         "hermes": HermesDetector,
+        "gigachat3": GigaChat3Detector,
     }
 
     def __init__(self, tools: List[Tool], tool_call_parser: str):
diff --git a/python/sglang/srt/function_call/gigachat3_detector.py b/python/sglang/srt/function_call/gigachat3_detector.py
new file mode 100644
index 000000000..ef94bdf9a
--- /dev/null
+++ b/python/sglang/srt/function_call/gigachat3_detector.py
@@ -0,0 +1,209 @@
+import json
+import logging
+import re
+from typing import List
+
+from sglang.srt.entrypoints.openai.protocol import Tool
+from sglang.srt.function_call.base_format_detector import BaseFormatDetector
+from sglang.srt.function_call.core_types import (
+    StreamingParseResult,
+    ToolCallItem,
+    _GetInfoFunc,
+)
+
+logger = logging.getLogger(__name__)
+
+REGEX_FUNCTION_CALL = re.compile(
+    r"function call<\|role_sep\|>\n(.*)",
+    re.DOTALL,
+)
+
+REGEX_CONTENT_PATTERN = re.compile(
+    r"^(.*?)<\|message_sep\|>",
+    re.DOTALL,
+)
+
+NAME_REGEX = re.compile(
+    r'"name"\s*:\s*"([^"]*)"',
+    re.DOTALL,
+)
+
+ARGS_REGEX = re.compile(
+    r'"arguments"\s*:\s*(.*)',
+    re.DOTALL,
+)
+
+
+class GigaChat3Detector(BaseFormatDetector):
+    def __init__(self) -> None:
+        super().__init__()
+        self.tool_started: bool = False
+        self.tool_name_sent: bool = False
+        self.end_content: bool = False
+        self._buffer: str = ""
+        self.prev_tool_call_arr: list[dict] = []
+
+    def has_tool_call(self, text: str) -> bool:
+        """Check if text contains a tool call marker"""
+        return "function call<|role_sep|>\n" in text
+
+    def detect_and_parse(
+        self,
+        text: str,
+        tools: List[Tool],
+    ) -> StreamingParseResult:
+        """
+        Non-streaming parsing of complete model output.
+        Extracts tool calls and content from the full text.
+        """
+        logger.debug(f"[GigaChat3] detect_and_parse: {text}")
+        model_output = text
+        function_call = None
+        content = None
+        if model_output.rstrip().endswith("</s>"):
+            model_output = model_output[: model_output.rfind("</s>")]
+        m_func = REGEX_FUNCTION_CALL.search(model_output)
+        if m_func:
+            try:
+                function_call = json.loads(m_func.group(1), strict=False)
+                if not (
+                    isinstance(function_call, dict)
+                    and "name" in function_call
+                    and "arguments" in function_call
+                ):
+                    function_call = None
+                elif not isinstance(function_call["arguments"], dict):
+                    function_call = None
+            except json.JSONDecodeError as e:
+                logger.warning(f"[GigaChat3] JSON decode error: {e}")
+                return StreamingParseResult(
+                    normal_text=model_output,
+                    calls=[],
+                )
+        m_content = REGEX_CONTENT_PATTERN.search(model_output)
+        if m_content:
+            content = m_content.group(1)
+        else:
+            if "<|message_sep|>" in model_output:
+                content = model_output.split("<|message_sep|>")[0]
+            else:
+                content = model_output
+        if not function_call:
+            return StreamingParseResult(normal_text=content, calls=[])
+        name = function_call["name"]
+        args = function_call["arguments"]
+        match_result = {"name": name, "arguments": args}
+        calls = self.parse_base_json(match_result, tools)
+        return StreamingParseResult(normal_text=content, calls=calls)
+
+    def parse_streaming_increment(
+        self,
+        new_text: str,
+        tools: List[Tool],
+    ) -> StreamingParseResult:
+        """
+        Streaming parser for incremental text chunks.
+        Maintains state across calls to build complete tool calls.
+        """
+        if not new_text:
+            return StreamingParseResult()
+        logger.debug(f"[GigaChat3] parse_streaming_increment: '{new_text}'")
+        self._buffer += new_text
+        current_text = self._buffer
+        delta_text = new_text
+        content = None
+        func_name = None
+        cur_args = None
+        m_func = REGEX_FUNCTION_CALL.search(current_text)
+        if not self.tool_started:
+            m_content = REGEX_CONTENT_PATTERN.search(delta_text)
+            if m_content:
+                content = m_content.group(1)
+                self.end_content = True
+            else:
+                if "<|message_sep|>" in delta_text:
+                    content = delta_text.split("<|message_sep|>")[0]
+                    self.end_content = True
+                else:
+                    if not self.end_content:
+                        content = delta_text
+            if m_func:
+                self.tool_started = True
+                logger.debug("[GigaChat3] Tool call started")
+            if content:
+                return StreamingParseResult(normal_text=content)
+        if not m_func:
+            return StreamingParseResult()
+        json_tail = m_func.group(1).strip()
+        name_match = NAME_REGEX.search(json_tail)
+        if name_match:
+            func_name = name_match.group(1)
+        args_match = ARGS_REGEX.search(json_tail)
+        if args_match:
+            cur_args = args_match.group(1).strip()
+            if cur_args.endswith("</s>"):
+                cur_args = cur_args[: -len("</s>")]
+            if cur_args.endswith("}"):
+                try:
+                    candidate = cur_args[:-1].strip()
+                    json.loads(candidate, strict=False)
+                    cur_args = candidate
+                except json.JSONDecodeError:
+                    pass
+        calls: List[ToolCallItem] = []
+        if not self.prev_tool_call_arr:
+            self.prev_tool_call_arr.append({})
+        if not self.tool_name_sent:
+            if not func_name:
+                return StreamingParseResult()
+            self.tool_name_sent = True
+            self.prev_tool_call_arr[0]["name"] = func_name
+            logger.debug(f"[GigaChat3] Sending tool name: {func_name}")
+            calls.append(
+                ToolCallItem(
+                    tool_index=0,
+                    name=func_name,
+                    parameters="",
+                )
+            )
+            return StreamingParseResult(calls=calls)
+        if cur_args is None:
+            return StreamingParseResult()
+        prev_args = self.prev_tool_call_arr[0].get("arguments_str", "")
+        if not prev_args:
+            delta_args = cur_args
+        elif cur_args.startswith(prev_args):
+            delta_args = cur_args[len(prev_args) :]
+        else:
+            logger.warning(
+                f"[GigaChat3] Arguments overlap mismatch. "
+                f"prev='{prev_args[:50]}...' cur='{cur_args[:50]}...'"
+            )
+            return StreamingParseResult()
+        if not delta_args:
+            return StreamingParseResult()
+        self.prev_tool_call_arr[0]["arguments_str"] = cur_args
+        try:
+            args_dict = json.loads(cur_args, strict=False)
+            self.prev_tool_call_arr[0]["arguments"] = args_dict
+        except json.JSONDecodeError:
+            self.prev_tool_call_arr[0]["arguments"] = {}
+        logger.debug(f"[GigaChat3] Sending args delta: '{delta_args[:100]}...'")
+        calls.append(
+            ToolCallItem(
+                tool_index=0,
+                name=None,
+                parameters=delta_args,
+            )
+        )
+        return StreamingParseResult(calls=calls)
+
+    def supports_structural_tag(self) -> bool:
+        """GigaChat3 does not use structural tags"""
+        return False
+
+    def structure_info(self) -> _GetInfoFunc:
+        """Not applicable for GigaChat3"""
+        raise NotImplementedError(
+            "GigaChat3Detector does not support structural_tag format."
+        )
diff --git a/test/registered/function_call/test_function_call_parser.py b/test/registered/function_call/test_function_call_parser.py
index 7263a492c..126d68e5d 100644
--- a/test/registered/function_call/test_function_call_parser.py
+++ b/test/registered/function_call/test_function_call_parser.py
@@ -6,6 +6,7 @@ from sglang.srt.function_call.base_format_detector import BaseFormatDetector
 from sglang.srt.function_call.core_types import StreamingParseResult
 from sglang.srt.function_call.deepseekv3_detector import DeepSeekV3Detector
 from sglang.srt.function_call.deepseekv32_detector import DeepSeekV32Detector
+from sglang.srt.function_call.gigachat3_detector import GigaChat3Detector
 from sglang.srt.function_call.glm4_moe_detector import Glm4MoeDetector
 from sglang.srt.function_call.glm47_moe_detector import Glm47MoeDetector
 from sglang.srt.function_call.json_array_parser import JsonArrayParser
@@ -3205,5 +3206,510 @@ class TestLfm2Detector(unittest.TestCase):
         self.assertEqual(info.trigger, "<|tool_call_start|>")
 
 
+class TestGigaChat3Detector(unittest.TestCase):
+    def setUp(self):
+        self.tools = [
+            Tool(
+                type="function",
+                function=Function(
+                    name="manage_user_memory",
+                    description="Create, update, or delete a user memory entry.",
+                    parameters={
+                        "type": "object",
+                        "properties": {
+                            "content": {
+                                "anyOf": [{"type": "string"}, {"type": "null"}],
+                                "default": None,
+                            },
+                            "action": {
+                                "type": "string",
+                                "enum": ["create", "update", "delete"],
+                                "default": "create",
+                            },
+                            "id": {
+                                "anyOf": [
+                                    {"type": "string", "format": "uuid"},
+                                    {"type": "null"},
+                                ],
+                                "default": None,
+                            },
+                        },
+                    },
+                ),
+            ),
+            Tool(
+                type="function",
+                function=Function(
+                    name="get_weather",
+                    description="Get weather information",
+                    parameters={
+                        "type": "object",
+                        "properties": {
+                            "city": {"type": "string", "description": "City name"},
+                            "unit": {
+                                "type": "string",
+                                "enum": ["celsius", "fahrenheit"],
+                            },
+                        },
+                        "required": ["city"],
+                    },
+                ),
+            ),
+        ]
+        self.detector = GigaChat3Detector()
+
+    def test_has_tool_call(self):
+        """Test detection of tool call markers."""
+        self.assertTrue(self.detector.has_tool_call("function call<|role_sep|>\n{}"))
+        self.assertFalse(self.detector.has_tool_call("No tool call here"))
+
+    def test_detect_and_parse_no_tool_call(self):
+        """Test parsing text without tool calls."""
+        text = "How can I help you today?"
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        self.assertEqual(result.normal_text, text)
+        self.assertEqual(len(result.calls), 0)
+
+    def test_detect_and_parse_simple_tool_call(self):
+        """Test parsing a simple tool call without content."""
+        text = '<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory", "arguments": {"action": "create", "id": "preferences"}}'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        # No content before tool call
+        self.assertEqual(result.normal_text, "")
+        self.assertEqual(len(result.calls), 1)
+        self.assertEqual(result.calls[0].name, "manage_user_memory")
+
+        params = json.loads(result.calls[0].parameters)
+        self.assertEqual(params["action"], "create")
+        self.assertEqual(params["id"], "preferences")
+
+    def test_detect_and_parse_parameterless_tool_call(self):
+        """Test parsing a tool call with empty arguments."""
+        text = '<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory", "arguments": {}}'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        self.assertEqual(result.normal_text, "")
+        self.assertEqual(len(result.calls), 1)
+        self.assertEqual(result.calls[0].name, "manage_user_memory")
+
+        params = json.loads(result.calls[0].parameters)
+        self.assertEqual(params, {})
+
+    def test_detect_and_parse_complex_tool_call(self):
+        """Test parsing a tool call with nested objects."""
+        text = """<|message_sep|>
+
+function call<|role_sep|>
+{"name": "manage_user_memory", "arguments": {"action": "create", "id": "preferences", "content": {"short_answers": true, "hate_emojis": true, "english_ui": false, "russian_math_explanations": true}}}"""
+
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        self.assertEqual(result.normal_text, "")
+        self.assertEqual(len(result.calls), 1)
+        self.assertEqual(result.calls[0].name, "manage_user_memory")
+
+        params = json.loads(result.calls[0].parameters)
+        self.assertEqual(params["action"], "create")
+        self.assertEqual(params["id"], "preferences")
+        self.assertIsInstance(params["content"], dict)
+        self.assertEqual(params["content"]["short_answers"], True)
+        self.assertEqual(params["content"]["hate_emojis"], True)
+
+    def test_detect_and_parse_with_content_before(self):
+        """Test parsing tool call with text content before it."""
+        text = 'I\'ll check that for you.<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory", "arguments": {"action": "create", "id": "preferences"}}'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        self.assertEqual(result.normal_text, "I'll check that for you.")
+        self.assertEqual(len(result.calls), 1)
+        self.assertEqual(result.calls[0].name, "manage_user_memory")
+
+    def test_detect_and_parse_with_eos_token(self):
+        """Test parsing tool call with EOS token at the end."""
+        text = '<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory", "arguments": {"action": "create", "id": "preferences"}}</s>'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        self.assertEqual(result.normal_text, "")
+        self.assertEqual(len(result.calls), 1)
+        self.assertEqual(result.calls[0].name, "manage_user_memory")
+
+        params = json.loads(result.calls[0].parameters)
+        self.assertEqual(params["action"], "create")
+        self.assertEqual(params["id"], "preferences")
+
+    def test_detect_and_parse_with_content_and_eos(self):
+        """Test parsing tool call with content and EOS token."""
+        text = 'I\'ll remember that.<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory", "arguments": {"action": "create", "id": "test"}}</s>'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        self.assertEqual(result.normal_text, "I'll remember that.")
+        self.assertEqual(len(result.calls), 1)
+        self.assertEqual(result.calls[0].name, "manage_user_memory")
+
+    def test_detect_and_parse_invalid_json(self):
+        """Test parsing with invalid JSON in function call."""
+        text = '<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory", "arguments": {invalid json}}'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        # Should return the full text as content when JSON parsing fails
+        self.assertIn("function call", result.normal_text)
+        self.assertEqual(len(result.calls), 0)
+
+    def test_detect_and_parse_missing_name(self):
+        """Test parsing with missing function name."""
+        text = '<|message_sep|>\n\nfunction call<|role_sep|>\n{"arguments": {"action": "create"}}'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        # Should not extract tool call if name is missing
+        self.assertEqual(len(result.calls), 0)
+
+    def test_detect_and_parse_missing_arguments(self):
+        """Test parsing with missing arguments field."""
+        text = '<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory"}'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        # Should not extract tool call if arguments is missing
+        self.assertEqual(len(result.calls), 0)
+
+    def test_detect_and_parse_arguments_not_dict(self):
+        """Test parsing with arguments that is not a dict."""
+        text = '<|message_sep|>\n\nfunction call<|role_sep|>\n{"name": "manage_user_memory", "arguments": "string_args"}'
+        result = self.detector.detect_and_parse(text, self.tools)
+
+        # Should not extract tool call if arguments is not a dict
+        self.assertEqual(len(result.calls), 0)
+
+    def test_streaming_no_tool_call(self):
+        """Test streaming text without tool calls."""
+        chunks = ["How ", "can ", "I ", "help ", "you?"]
+
+        accumulated_text = ""
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+            accumulated_text += result.normal_text
+
+        self.assertEqual(accumulated_text, "How can I help you?")
+        self.assertEqual(len(result.calls), 0)
+
+    def test_streaming_simple_tool_call(self):
+        """Test streaming a simple tool call."""
+        chunks = [
+            "<|message_sep|>\n\n",
+            "function call",
+            "<|role_sep|>\n",
+            '{"name": "manage_user_memory", ',
+            '"arguments": {"action": "create"',
+            ', "id": "preferences"}}',
+        ]
+
+        tool_calls_by_index = {}
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "manage_user_memory")
+
+        params = json.loads(tool_calls_by_index[0]["parameters"])
+        self.assertEqual(params["action"], "create")
+        self.assertEqual(params["id"], "preferences")
+
+    def test_streaming_with_content_before(self):
+        """Test streaming with content before tool call."""
+        chunks = [
+            "I'll ",
+            "help ",
+            "you.",
+            "<|message_sep|>\n\n",
+            "function call",
+            "<|role_sep|>\n",
+            '{"name": "get_weather", ',
+            '"arguments": {"city": "Tokyo"}}',
+        ]
+
+        accumulated_text = ""
+        tool_calls_by_index = {}
+
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+            accumulated_text += result.normal_text
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        self.assertEqual(accumulated_text, "I'll help you.")
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "get_weather")
+
+        params = json.loads(tool_calls_by_index[0]["parameters"])
+        self.assertEqual(params["city"], "Tokyo")
+
+    def test_streaming_complex_arguments(self):
+        """Test streaming with complex nested arguments."""
+        chunks = [
+            "<|message_sep|>\n\n",
+            "functi",
+            "on call<|role_sep|>\n",
+            '{"name": "manage_user_memory", "arguments": ',
+            '{"action": "create", "id": "prefs", ',
+            '"content": {"likes": ["short", "clear"], ',
+            '"dislikes": ["emojis", "verbose"]}',
+            "}}",
+        ]
+
+        tool_calls_by_index = {}
+
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "manage_user_memory")
+
+        params = json.loads(tool_calls_by_index[0]["parameters"])
+        self.assertEqual(params["action"], "create")
+        self.assertEqual(params["content"]["likes"], ["short", "clear"])
+        self.assertEqual(params["content"]["dislikes"], ["emojis", "verbose"])
+
+    def test_streaming_with_eos_token(self):
+        """Test streaming with EOS token at the end."""
+        chunks = [
+            "<|message_sep|>\n\n",
+            "function c",
+            "all<|role_sep|>\n",
+            '{"name": "get_weather", ',
+            '"arguments": {"city": "Paris"}}',
+            "</s>",
+        ]
+
+        tool_calls_by_index = {}
+
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "get_weather")
+
+        params = json.loads(tool_calls_by_index[0]["parameters"])
+        self.assertEqual(params["city"], "Paris")
+
+    def test_streaming_incomplete_json(self):
+        """Test streaming with incomplete JSON (no closing brace)."""
+        chunks = [
+            "<|message_sep|>\n\n",
+            "fun",
+            "ction call<|role_sep|>\n",
+            '{"name": "get_weather", ',
+            '"arguments": {"city": "London"',
+            # Missing closing braces
+        ]
+
+        tool_calls_by_index = {}
+
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        # Should have name but incomplete parameters
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "get_weather")
+        self.assertTrue(tool_calls_by_index[0]["parameters"].startswith('{"city":'))
+
+    def test_streaming_large_steps(self):
+        """Test streaming with large chunks that complete in fewer steps."""
+        chunks = [
+            "I'll remember that.",
+            "<|message_sep|>\n\nfuncti",
+            "on call<|role_sep|>\n",
+            '{"name": "manage_user_memory", "arguments": {"action": "create", "id": "preferences", "content": {"short_answers": true, "hate_emojis": true, ',
+            '"english_ui": false, "russian_math_explanations": true}',
+            "}}",
+        ]
+
+        accumulated_text = ""
+        tool_calls_by_index = {}
+
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+            accumulated_text += result.normal_text
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        self.assertEqual(accumulated_text, "I'll remember that.")
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "manage_user_memory")
+
+        params = json.loads(tool_calls_by_index[0]["parameters"])
+        self.assertEqual(params["action"], "create")
+        self.assertEqual(params["content"]["short_answers"], True)
+        self.assertEqual(params["content"]["russian_math_explanations"], True)
+
+    def test_streaming_very_small_chunks(self):
+        """Test streaming with very small chunks (character by character)."""
+        text = '{"name": "get_weather", "arguments": {"city": "NYC"}}'
+
+        # Split into very small chunks (every 5 characters)
+        chunk_size = 5
+        chunked_text = [
+            text[i : i + chunk_size] for i in range(0, len(text), chunk_size)
+        ]
+        chunks = [
+            "<|message_sep|>\n\n",
+            "func",
+            "tion call",
+            "<|role_sep|>\n",
+            *chunked_text,
+        ]
+        tool_calls_by_index = {}
+
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "get_weather")
+
+        params = json.loads(tool_calls_by_index[0]["parameters"])
+        self.assertEqual(params["city"], "NYC")
+
+    def test_streaming_json_split_at_quotes(self):
+        """Test streaming when JSON is split at quote boundaries."""
+        chunks = [
+            "<|message_sep|>\n\nfunction call<|role_sep|>\n",
+            '{"name',
+            '": "',
+            "get_weather",
+            '", "arguments',
+            '": {"city',
+            '": "',
+            "Rome",
+            '"}}',
+        ]
+
+        tool_calls_by_index = {}
+
+        for chunk in chunks:
+            result = self.detector.parse_streaming_increment(chunk, self.tools)
+
+            for call in result.calls:
+                if call.tool_index is not None:
+                    if call.tool_index not in tool_calls_by_index:
+                        tool_calls_by_index[call.tool_index] = {
+                            "name": "",
+                            "parameters": "",
+                        }
+
+                    if call.name:
+                        tool_calls_by_index[call.tool_index]["name"] = call.name
+                    if call.parameters:
+                        tool_calls_by_index[call.tool_index][
+                            "parameters"
+                        ] += call.parameters
+
+        self.assertEqual(len(tool_calls_by_index), 1)
+        self.assertEqual(tool_calls_by_index[0]["name"], "get_weather")
+
+        params = json.loads(tool_calls_by_index[0]["parameters"])
+        self.assertEqual(params["city"], "Rome")
+
+
 if __name__ == "__main__":
     unittest.main()